Buttonhole sewing machine



8 Sheets-Sheet 1 July 13, 1943. J. H. PlKUL BuTToNHoLE SEWING MACHINE Filed Jan. 51, 1941 July 13, 1943. J. H. PIKUL BUTTONHOLE SEWING MACHINE Filed Jan. 31, 1941 8 Sheets-Sheet 2 I J. H. PIKUL BUTTONHOLE SEWING MACHINE July V13, 1943.

8 Sheets-Sheet 5 Eiled Jan. 51, 1941 July 13, 1943. J. H. PlKul. v 2,324,235

BUTTONHOLE SEWING MCHINE Filed Jan. 3l, 1941 8 Sheets-Sheet 4 i la@ lNvEN-Fcq R l l l x "July 13, 1943. J. H. PIKUL BUTTONHOLE SEWING MACHINE 8 Sheets-Sheet 5 DAW INVENMDR July 13, 1943. l J. H, P|KUL 2,324,235

BUTTONHOLE SEWING MACHINE July 13, 1943. J. H. PIKUL BUTTONHOLE SEWING MACHINE Filed Jan. .'51, 1941 lll 8 Sheets-Sheet 8 J. H. PIKUL BUTT'ONHOLE SEWING MACHINE Filed Jan. 31, 1941 July 13, 1943.

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Patented July 13, 1943 UNITED STATES lPATE-:NT OFFICE 2,324,235 BUTTONHOLE SEWING MACHINE Joseph H. Pikul, West Newton, Mass.

Application January 31, 1941, Serial No. 376,716

(Cl. i12- 71) 42 Claims.

This invention relates to buttonhole sewing machines, and especially to the trimming of thread and cord used in the sewing of buttonholes, particularly, although not exclusively, that type of buttonhole known as the eyelet end buttonhole, by which is meant a buttonhole having substantially radially disposed stitches around one end, whether said end is enlarged to form an eye proper or not. A stay cord is usually sewn around the contour of the eyelet end type buttonhole.

The invention has for its general objects to provide for automatically causing the ends of the stay cord, when one is used, to be sewn in or covered by the stitching, and also to provide for the automatic trimming of the sewing thread at the end of the stitching in buttonholes of different lengths, as well as to provide for a proper length of sewing thread to start the sewing of a succeeding buttonhole irrespective of the length of the buttonhole previously sewn.

The eyelet end type buttonhole can be divided into two main classes; (l) the open end buttonhole and (2) the fly bar buttonhole.

The open end buttonhole is the type in which the end of the buttonhole away from the eye is not closed until a second operation is performed called tacking. This tacking operation consists in sewing stitches across the open end of the buttonhole, thus closing the end and fastening both sides of the buttonhole together. This buttonhole, therefore, has a nished end perpendicular to the length of the buttonhole.

The y bar buttonhole is the type in which the side stitches are superimposed at the end away from the eye. This closure therefore comprises a group of stitches extending parallel to the sides of the buttonhole.

To make a clean neat bar on the open end type of buttonhole, a convenient length of cord and thread have been left at the end of the buttonhole. When the tack was made, these ends were pulled through the buttonhole slit so that they appeared under the tack on the reverse side. They were then trimmed by hand. It was not practical to trim the ends by hand close enough to the end stitches of the buttonhole so that the tack could conceal them; and heretofore, it has not been possible by machine trimming, The pulling of the two cord ends and thread through the slit causes it to bulge around them. Obviousiy this b-ulge distorts the buttonhole. Prior to the present invention, there has been no completely satisfactory method or mechanism for' trimming the cord and thread of open end bu*- tonholes.

In fly bar buttonholes the cord ends have been sewn in by the superimposed stitches of the bar which are arranged in a series extending parallel to the lengthwise direction of the buttonhole. There Vhas always been a cord end protruding from the fly bar whether the cord was trimmed by machine or by hand, because the trimming was necessarily done after the last stitch had been sewn. The present invention makes, it entirely possible to completely cover the ends of the cord by stitches.

A machine constructed in accordance with this invention can be adjusted to sew either of the above types of buttonholes, It will sew either of these types of buttonholes in any length desired Within the capacity of the machine. Heretofore, in machines adjustable to sew variable length buttonholes, it has been impossible to trim the cordor thread without leaving different lengths of cord or thread protruding from the end of the buttonhole. If the buttonhole was long, these lengths were short, and if the buttonhole was short, they Were long. The present invention makes it possible to trim the cord for open end buttonholes so that the tack will cover the ends. In fly bar buttonholes it makes it possible to conceal the ends of the cord Within the stitching of the y bar. It also accomplishes this in either type of buttonhole regardless of its length. In short, the invention makes possible such cord trimming that buttonholes of variable lengths, either of the open end type or of the fly bar type, may be so trimmed that the ends of the cord are the same length, either protruding by exactly the required amount or covered by 4stitches with respect t0 the end of the buttonhole; and to this end, in accordance with one feature of the invention, there is provided cord trimming mechanism which operates to predetermine the length of cord required in accordance with the length of the buttonhole and to cut 01T that length before the stitching is completed. The invention also makes it possible, in sewing buttonholes of different lengths, to automatically trim the thread at a substantially constant or predetermined distance from the end of the stitching, so as not to leave protruding thread ends, and to provide the proper lengths oi threads to start the sewing of the next buttonhole, al1 irrespective of the length of the buttonhole sewn.

In accordance with the invention the cord and thread trimming mechanisms above referred to, are automatically set to operate in accordance With the length of the buttonhole, so that a single adjustment suffices to set the machine to sew buttonholes of any desired length, to supply just the proper length of cord to be properly bound in, to trim the thread at the end of the stitching, and to leave thread ends of measured or substantially constant length suitable for starting the stitching of the next buttonhole.

The foregoing and other objects of the invention, together with means whereby the latter may be carried into effect, will best be understood from the following description of an illustrative embodiment thereof shown in the accompanying drawings, this, however, having been chosen for purposes of exemplication merely,

as it will be obviouse to those skilled in the art that said invention, as defined by the claims hereunto appended, may be otherwise embodied Without departure from its spirit and scope.

In said drawings:

Fig. 1 is a side elevation, partly in section, of a buttonhole sewing machine having incorporated therein mechanism embodying the present invention, the parts being shown in position just prior to the beginning of the stitching operation or cycle;

Figs. 2 and 3 are vertical sections taken respectively on the lines 2 2 and 3 3 of Fig. 1;

Fig. 4 is a top plan view of the machine with some of the parts omitted, and the parts shown being in the position corresponding to Fig. 1;

Fig. 5 is an enlarged vertical section taken on the line 5 5 of Fig, 1;

Figs. 5a, 5b and 5c are fragmentary views illustrating different positions of certain parts shown in Fig. 5;

Fig. 5d is a fragmentary plan View of the parts shown in Fig. 5a;

Fig. 6 is a vertical section taken on the line 6 6 of Fig. 1;

Fig. 7 is a top plan View of the lower turret shown in Fig. 5, some of the parts being omitted;

Fig. 8 is a fragmentary elevation of the lower turret, partly in section on the line 8 8 of Fig. 7;

Fig. 9 is a horizontal section taken on the line 9 9 of Fig. 8, some parts being omitted;

Fig. 10 is a plan View and Fig. 11 a side elevation, partly in section, of certain of the parts show-n in Fig. 5, the turret and its associated parts being reversed from the position shown in Fig. 4 as the stitching cycle is being completed;

Fig. 12 is an enlarged front elevation of the parts shown in Figs. 10 and 1l;

Fig. 13 is a vertical section taken on the line |3 l3 of Fig. 12';

Fig. 14 is a horizontal section taken on line |4 l4 of Fig. 12;

Fig. 15 is a view similar to Fig. 13 but showing the cord supplying guide in retracted position;

Fig. 16 is a vertical section taken on the line |6 l'6 of Fig. 15, illustrating the cord severing operation;

Fig. 17 is a view similar to Figs. 13 and 15 but showing the cord guide returned to its normal position;

Fig. 18 is a perspective view andFig. 19 a longitudinal vertical section of the throat plate;

Fig. 20 is a fragmentary, diagrammatic perspective view showing the relation of the upper and under threads to the stitch-forming mechanism at the completion of the stitching cycle, the parts being partly enlarged and their relative positions somewhat distorted to illustrate more clearly the action as the stitching cycle is about to be completed;

Fig. 21 is a bottom plan View showing the condition of the under side of the work at the oompletion of the stitching cycle;

Fig. 22 is a perspective View similar to Fig. 20 of the parts shown therein, the view being taken from .a different angle.

Figs. 23 and 24 are perspective views similar respectively to those shown in Figs. 20 and 22, but showing the parts further advanced in the operative cycle; and

Figs. 25 and 26 are perspective views similar to those of Figs. 20 and 23 but showing respectively ,the action of the thread trimming mechanism as the upper thread is broken and the under thread is severed.

The invention is herein shown as embodied in an adjustable fly bar machine of the type described in Patent No. 2,072,991, March 9, 1937. Such a machine comprises a stationary Workholding or bed frame 30 carrying clamps 3| for holding the work W in which buttonholes are to be formed, and a movable stitching frame 32 carrying the stitching instrumentalities and buttonhole cutting instrumentalities 33, together with mechanism for imparting the necessary movements to the stitching frame to position the stitches and for other purposes.

The stitching instrumentalities comprise a needle bar 34 carrying an eye-pointed needle 35 for supplying an upper thread t and underthread handling mechanism which, as herein shown, is of the general type described, for example, in Patents No. 862,238, August 6, 1907, No. 1,743,356, January 14, 1930, and No. 1,905,854, April 25, 1933, and comprises an oscillating lcoper carrier 36 (Fig. 5) carrying a pair of loopers 31 and cooperating loop spreaders 38, one of said loopers having an eye 39 (Figs. 23 to 26) for supplying an under-thread t. The stitching instrumentalities are operated through suitable connections from a stitching shaft 40 which is periodically connected with a driving pulley 4I through a stop mechanism generally indicated at 42 and controlled by a normally fixed but longitudinally adjustable cam bar 43 carried by the bed frame 30. The cam bar 43 has a raised portion 45 which, during the movement of the stitching frame in one direction, cooperates with a roller 44 (Fig. 1) to connect the driving pulley with the stitching shaft and start the stitching operation, and also with an end shoulder 45 which, during the movement of the stitching frame in the opposite direction, is engaged by a latch 41 to cause disconnection of said pulley and shaft and stop the stitching operation, all as is well known in the art and described, for example, in Patent No. 713,764, November 18, 1902. The needle bar 34 and the under-thread mechanism are carried respectively by upper and lower turrets 5| and 52 which are rotated or turned through in sewing around the eye end of the buttonhole and are returned to their original angular position just prior to the completion of the cycle of operations of the machine, the rotation of said turrets being effected by gear segments 5l and 58 carried by a vertical rock shaft 59 operated by a main cam 53, hereinafter referred to, all as is well known in the art and shown in numerous prior patents, for example Patent' No. 349,359, September 21, 1886.

It will be understood that in machines of this general type the stitching frame 32 has a xed range of movement, rearwardly and forwardly,

upon the bed frame 30 longitudinally of the buttonhole, the rst part of this movement in the rearward direction being a relatively rapid one to carry the stitching frame from the buttonhole cutting to stitching position, (while the stitching mechanism is inactive), followed by a relatively slow movement (with the stitching mechanism in operation) to position the stitches about the buttonhole, first along one side of the buttonhole, then around the eye end of the buttonhole, and then in the forward direction along the other side, completed (after the stopping of the stitching mechanism) by a final relatively rapid forward movement to return the parts from stitching to buttonhole cutting position. rlhis movement is derived from the main cam 53 (Figs. 1 and 4) carried by the stitching frame and driven through worm gearing from a shaft 54 journalled in said frame, said cam having in its upper face a cam groove to receive a pin 55 rigid with the bed frame 3G. The main cam 53 also has portions for operating the cutting mechanism 33 at the proper time as well as the mechanism for rotating the turrets 5| and 52. Said main cam 53 is further formed with a cam groove 5S (Fig. 1) cooperating with suitable mechanism for imparting tothe stitching frame the lateral feed movements which, in conjunction with the rotation of the turrets, serves to position the stitches around the eye end of the buttonhole. The length of the buttonhole depends upon the point in the longitudinal travel at which the stitching operation is started and stopped, and this, in turn, is controlled by the position of the cam bar 43. In Fig. 1 the parts are shown in the position assumed thereby at a point during the rearward movement of the stitching frame just prior to the beginning of the stitching operation.

Except as hereinafter pointed out, and as it enters into combination with parts hereinafter referred to, the mechanism as thus far described is well known in the art, forms no portion of the present invention, and requires no further dedescription in detail.

Where a so-called fly bar is to be formed, the stitching frame may be given the necessary lateral feed movements at the beginning and end of the stitching operation by mechanism substantially like that described .in Patent No. 2,072,991, above referred to. This mechanism comprises a, fly bar cam plate 65 on. the bed frame 30 adjacent the rear end thereof and longitudinally adjustable thereon with the cam bar 42, said cam plate 65 having cam grooves 66 and 61 alternatively engaged by a pair of cam follower pins 68 and 59 carried by a block 'l0 pivoted at 'H to an extension F2 of the stitching frame 32, said block carrying at the opposite side of the pivot 1| from the follower pins 68 and 69 a roller 'I3 which, during the longitudinal movement of the stitch frame, except when sewing the eye, travels in a straight groove 'M formed in a cover plate 'i5 which encloses the rear end of the y bar cam plate 65. As more fully explained in Patent No, 2,072,991, during the first part of the rearward movement of the stitching frame, from buttonhole cutting to stitching position, the pin 68 moves in a straight forward portion a of the cam groove G5, then enters and traverses an offset portion c thereof, and is then raised from said groove by an inclined surface c therein, causing the pin 59 to enter the straight rear portion a' of the groove 51 which it traverses rearwardly and then forwardly during the sewing of the straight sides and around the eye end of the buttonhole, then entering and traversing an ofiset portion c' of said groove, being finally raised from said groove by an inclined surface e', causing the pin 68 to re-enter the portion a of the groove 66. The interconnection between the pins 68 and 69, whereby they are caused to alternatively engage their respective cam grooves, as shown in Fig. 2, is specically different from that shown in Patent No. 2,072,991, being substantially as described in Patent No. 2,134,417, October 25, 1938..

As herein shown, the cam plate S5 is mounted in a carrier 8| with which it is interengaged at its forward end, as indicated at 80 in Figs. 1 and 4, and to which it is secured at its rear end by bolts 02. The carrier 8| is guided in a way 83 formed in the top of the bed frame 30, and

has at its forward end an extension 84 connected by a screw with a boss 86 rising from a laterally offset portion 81 (Fig. 4) adjacent the rear endof a link 88. Adjacent its forward end the link 8B is formed with an oppositely offsetportion E9 connected by a screw 90 with a second link or slide 9| guided for longitudinal movement on vthe under side of the bed frame 39 (see Figs. 5 and 6). The link or slide 9i carries a rack 96 (Figs. l and 6) meshing with a pinion 97 on a .shaft 98 journalled in a bracket 99 secured by bolts |00 to the under side of the bed frame, said shaft having an operating knob lill. The bracket 99 is also formed with a slot |02 torreceive a clamping screw .|03 (Fig. 5) threaded into a depending portion |04 of the link 9| and having an operating handle'lil. Said link 9| is formed with an upstanding boss |05 (Figs. 1 and 4) connected by a screw |06 with a coupling |81 having a slot |09 through which it is adjustably connected with the cam bar i3 by a screw H0. Consequently, by releasing the clamping screw |03 and turning the knob IBI, the cam bar 43 and cam plate can be simultaneously adjusted to vary the length of vthe buttonhole without changing the length of the iiy bar, while by changing the position of the screw Ill vin the slot |99 the length of thev fiy bar'formed in a buttonhole of a given length can be varied, all in a manner substantially similar to' that described in Patent No. 2,072,991, above'referre'd to. By adjusting the last. named parts into an eX- treme position, the fly bar can be eliminated entirely and an open end buttonhole produced. In other words, if the screw ||0 be positioned sufficiently forwardly in the slot 09, the pin B8 will traverse the offset portion c of the cam groove 65 before the stitching commences, and the pin 69 will not enter the offset portion c'iof the cam groove 67 until after the stitching has stopped, so that during the lateral movements of the stitching frame which would normally produce a fiy bar, the stitching mechanism is idle and no fly bar is formed.

Carried by the lower turret 52 are stay cord supplying, cord trimming or cutting, and thread trimming instrumentalities, each having or including operating elements which', at suitable times during the forward travel of the stitching frame 32, are acted upon by actuating devices on said stitching frame, which devices, in turn, engage and are actuated by elements on the bed frame 30 as the former frame moves over the latter. During the rearward travel of the stitching frame, and consequently during the first part of the stitching operation, the angular position of the turret 52, as shown in Figs. 4 and 5, is such that the several operating elements are out of operative relation with their several actuating devices, so that said instrumentalities are not actuated during his part'of the cycle, but, when said turret is given its semi-rotation in sewing around the eye end of the buttonhole, said elements are brought into operative relation with said devices, so that said instrumentalities are actuated at the proper times (prior to or just after the completion of the stitching operation) during the return or forward travel of the stitching frame.

The turret 52 also carries a throat plate IIB (Figs. 4, 5, 7, 8, to 13, and 15 to 26) having an opening I l1 through which the needle passes and also formed with certain recesses, grooves, etc. (hereinafter described) to receive and/or cooperate with the several instrumentalities above referred to. Said throat plate is provided with lugs ||8 adjustably attached by screws ||9 (Figs. '1, 10 and 12) to a plate |20 (Figs. 12 and 13) hereinafter referred to, secured by screws I2| to the turret proper Referring particularly to Figs. 13, and 1'1, the stay cord supplying means or instrumentality comprises a rigid guide or tube |26 through which a stay cord C is supplied in a continuous length from a suitable source, not shown. The tube |26 is secured by a screw to a slide |21 movable in an arcuate path on a rib-like guide |28 (see also Fig. 14) secured to the turret 52. Movement, in a generally vertical direction, of the slide |21 on its guide |28 causes swinging movement of the tube 26, between the position shown in Figs. 13 and 17 and that shown in Fig. 15, in a recess 29 (see particularly Fig. 19) in the under side of the throat plate I6 and a groove |30 (seealso Fig. 18) in the upper face thereof, said groove communicating at one end with the recess |29 and at the opposite end with the needle opening |I1. For so moving the slide |21 it is connected by a link |3| with a sleeve |32 slidablsr mounted on a vertical post |33 carried by the turret 52, said sleeve being normally held in elevated position, to cause the tube |26 to assume the position shown in Figs. 13 and 1'7, by a spring |35 (Fig. 12) connecting a pin |43 carried thereby with the turret. The sleeve |32 is provided with a laterally projecting stud |34 which, when the turret 52 is in the angular position shown in Fig. 10 during the forward or return movement of the stitching frame 32, is in the path of downward movement of the inner end of a lever |36 pivoted intermediate its ends at |31 to the stitching frame (see also Fig. 5), but which, when said turret is in the angular position shown in Fig, 4, during the initial or rearward movement of said stitching frame, is out of the range of movement of said lever. During the longitudinal movement of the stitching frame, the outer end of the lever |36 engages a normally stationary cam |40 (Figs. 1, 5, 10, 11 and 12) secured, as by a screw I4I, to an adjustable bracket or slide |42 carried, as hereinafter described, by the bed frame, thereby lifting the outer end of said lever, depressing the inner end thereof, and causing said inner end, during the forward movement of the stitching frame, to engage the stud |34 and depress the sleeve |32. The inner end of the lever |36 is normally held in the elevated position shown in Fig. 12 by a spring |44 connecting the outer end thereof with a bracket |45 secured as hereinafter described to the stitching frame.

The slide I 21 carries a cord gripper comprising a pawl or jaw |39 so pivoted that, when the tube |26 moves from the position shown in Figs. 13 and 1'1 into the position shown in Fig. 15, said jaw moves idly over the cord C, but when said tube moves in the opposite direction said jaw grips the cord, causing it to move with the tube and be withdrawn from the supply.

Referring particularly to Figs. 8, 9, 13 and 15 to 19, the stay cord trimming or cutting instrumentalities comprise a pair of shear blades I5| located in a chamber |52 formed between the plate |20 and the body of the turret 52, said blades having their cooperating cutting ends operating in an opening |53 in the throat plate I|6 between the recess |29 and the groove |30, being therefore spaced from the needle opening II1, i. e., from the stitching point. The blades |5| are separately pivoted at |54 to the plate |20 and are formed with intersecting slots |55 which receive a stud |56 projecting laterally from the inner end of a lever |51 pivoted intermediate its ends at |58 to the turret 52. Movement of the lever |51 on its pivot, in a clockwise direction as shown in Fig. 16, causes the cutting ends of said blades to approach one another and sever the cord C extending between them when the tube |26 is in the position shown in Fig, 15, said ends being normally held separated to receive the tube |26 between them when said tube is in the position shown in Figs. 13 and 17, by a leaf spring |59 (Figs. 8 and 16) carried by the turret and engaging the lever |51 at the outer side of its pivot. The lever |51 carries at its outer end a roller |69 which, when the turret 52 is in the angular position shown in Fig. 10 (see also Figs. 11 and 12) during the forward or return movement of the stitching frame 32, is received between a pair of laterally projecting lips |6| on the upper end of a slide |62 (Figs. 5, 11 and 12) guided for vertical movement in a way formed in the face of the bracket |45 adjacent the stitching frame 32, said slide |62 being normally held in the elevated position shown in Fig. 12 by a spring |63 connecting a stud |64 thereon with a stud |65 on said bracket |45. When the turret 52 is in the angular position shown in Fig. 4 duringl the initial or rearward movement of the stitching frame, the roller 60 is disengaged from the lips |6I (see also Fig. 5). The slide |62 carries a cam roller |66 which, during the longitudinal movement of the stitching frame, engages a normally stationary cam |61 carried by the bracket |42, thereby depressing said slide (as shown in Fig. 5) and (during the forward movement of the stitching frame, when the roller |60 is engaged with the lips |6I) rocking the lever |51 from the position shown in Fig. 12 into that shown in Fig. 16 and operating the shears I5 I Referring particularly to Figs. 4, 5, 7, 10, 11, 25 and 26, the thread trimming instrumentalities comprise a lever |16 pivoted at |11 to the turret 52 to rock about a horizontal axis and having an upstanding arm |18 and a laterally extending arm |19. Adjustably secured, as by a screw |80, to the arm |18 of the lever |16 is the slotted angular shank |8| of a hook-like member |82 located adjacent the free end of the throat plate |I6, and secured by a screw |83 to -the shank |8I is a cutter |84 having an inclined cutting edge |85 disposed adjacent the hook |82. As shown most clearly in Figs. '1, 10, 25 and 26, the hook |92 is formed with a beak or edge p at the junction of an inclined upper face b thereof with an inclined front face b leading to the edge |85 of the cutter |84, said faces b and b diverging from the beak p. The lever |16 is normally held in the position shown in Figs, 5, 7, and 10, with the hook 82 at one side of the end of the throat plate, by a spring |86 (see Fig. 5) connecting the arm |18 thereof with the turret. The arm |19 of said lever is provided with a laterally projecting stud |81 Which, when the turret 52 is in the angular position shown in Fig. during the forward or return movement of the stitching frame 32, is in the path of upward movement vof the inner end of a lever |88 pivoted intermediate i-ts ends at |89 to a bracket |90 on the stitching frame. When the turret is in the angularposition shown in Fig. 4 (see also Fig. 5), during the initial or rearward movement of the stitching frame, the stud |81 is out of the path of movement of the lever |88. During the longitudinal movement of the stitching frame, the outer end of the lever |88 engages a normally stationary cam 9| secured to the bracket 42, thereby depressing the outer end of said lever, raising` the inner end thereof, and causing said inner end, during the forward movement of the stitching frame to engage the stud |81 and rock the lever |16. The lever |88 is normally held in the position shown in Fig. 5, with its innerv end depressed, by a torsion spring |92 (Figs. 10 and 11) associated with its pivot |89.

At the completion of the stitching operation, during the forward or return movement of the stitching frame, the relation of the stitching instrumentalities to the stitches s and work W, and the disposition of the upper thread t Vand under thread t with respect to said instrumentalities, are as shown in Figs. and 22. lAt this time, the final loop L of upper thread t is held by one of the loopers 31 and its coacting loop spreader 98 directly beneath the last sti-tch, so that said loop passes through the needle opening l I1 in the throat plate i6 without deflection. As the stitching frame continues to move forwardly out of stitching position, bringing the parts into the relative position shown in Fig. 23, bothlegs of the loop L Vare engaged by a lip |91 onthe` throat plate (see also Fig. 18) and deilected thereby into a shallow longitudinal groove |98 formed in said throat plate at one side of said lip, At 4thesarne time the under thread t', vheld Yby "thewother looper 31, is carried into aA deeper longitudinal groove |99 formed in the throat plate besidev the groove |98. This deflection of the upper and lower threads t and t' into the relatively shallow and deep grooves |98 and |99, respectively, causes a separation of the portions of said threads extending from the throat plate to the Work, as shown in Fig. 23. As the forward movement of the stitching frame continues, the outer end of the lever |88 engages the cam |9|, rocking said lever and consequently the lever |16, and causing the hook |82 and cutter |84 to move across the end ofthe throat plate from the position shown' in Figs. 5, '7 and 10, through that shown in Fig. 25, into that shown in Fig. 26. During this movement the beak p of the hook |82 passies under both legs of the loop L of upper thread t and over the under thread t', further separatingnsaid threads and causing the inclined front face b to force said under thread downwardlypullin g some thread through the throat plate from the,

supply, and forcing said thread against the edge of the cutter |84 and severing the same, as shown in Fig. 26, at the sametime causing the inclined., upper face b of said hook, which is sodisposed as to engage both legs of the loop L, to deflect or force both of said legs upwardly, stretching the, same over an edge of said face b until the leg dA of said loop, which leads tothe work and is under the greater tension, breaks, as likewise shown in Fig. 26, the other leg d leading to the needle providing sufficient thread to initiate the first stitch of the next buttonhole. If the edge of the face b over Which the thread is drawn be sufliciently sharp, the breakage will take place at said edge, as indicated in Fig. 26, or by making saidedge relatively dull, the thread may be caused to break at the knot or last stitch.

Figs. 20 and 22 to 26, being diagrammatic, are somewhat distorted for clearness of illustration. The Work is shown lifted from the throat plate (whereas it is actually in Contact with it at the times illustrated) and displaced laterally to show, approximately, the angles or directions of the threads. In actual practice, the hook |82 engages the threads much closer, relatively, to the work.

The arm |18 of the lever |15 is formed with a flange 280 (Figs. 5 and 7) to which is secured, as by screws 2M, a depending arm 282 carrying at its lower end an angular extension 293 adjustably secured thereto by a screw 224 passing through a slot in one arm of said extension, which slot also receives a stud 285 projecting from the arm 282. The other arm of the extension carries at its end a roller-288 for operating an under-thread handling device which acts, durin its initial movement, to apply a light tension to the under thread to prepare it for the severing operation (which tension is insufficient to cause said under thread'4 to snap out of the looper eye 39 after severing), and thereafter, and without materially increasing the tension, to pull from the supply a sufficient amount of under thread to initiate the firststitch of the next button hole. Said thread-handling device (Figs. 5, 5a, 5b and 5c) comprises a lever 281 pivoted at 28S to the turret 52 and normally Yheld inthe position shown in Fig. 5 by a spring 289 connecting a projection 2|!) thereon with a stud 2|! on said turret, said projection having a shoulder 2i? which engages the edge of the turret to limit movement under the inuence of said spring. 'Ihe lever 291 carries, adjacent the pivot v228 a bent thread-deflecting stud 2|3, and adjacent its free end, an angular plate or leaf 2id loosely connected by a stud 2|? with a bevelled face on the lever, guided by a pin 2|9 passing through an opening therein, and normallyrheld in the position shown in Fig. 5d by a spring 2|8. The under thread t passes from the source of supply through the usual tension (not shown) and about suitable guides includingra guide stud-H5 from which said thread passes to the looper eye 38 between the face of the lever 281 and the leaf 2|4 and at one side of the stud 2 I3. Said leaf 264 normally occupies the position shown in Figs.-5, 5a. and 5d, permitting the thread to pass freely between itself and said lever, but when deected into the position shown in Figs. 5b and 5c, as hereinafter described, acts to clamp said thread against said lever. rIhe lever 281 carries at its free end a curved tail piece 258 disposed in the the position shown-in l'lig.l 5b, causes Vthe thread to be clamped and to be deflected about the guide 2|3, thereby applying a light tension thereto for the action of the cutter 164. Thereafter further movement of the parts into the position shown in Fig. 5c causes a certain amount of thread, determined by the adjustment of the angular extension 203, to be drawn from the supply. It will be observed that this arrangement of the parts is such that as the lever 251 moves into the position shown in Fig. 5c it exerts a substantially direct pull upon the thread leading from the guide 2|5, but without, however (by reason of the proximity of the guide 2|3 to the pivot 208) exerting any substantial additional pull on the thread extending to the looper eye 36.

The complete operation of the machine, as thus far described, may be reviewed as follows. When the machine is started, with the stitching frame in its foremost or buttonhole cutting position, said frame moves rapidly rearwardly to the stitching position, the cam follower 63 (Fig. 4) moving in the straight portion a of the cam groove 66 until it reaches the offset portion c of said groove as shown in Fig. e, whereupon the stitching frame is swung laterally into the position to begin the sewing of the fiy-bar. The roller 44 (Fig. l) then engages the raised portion i5 of the cam bar 43, the stitching mechanism is started, and the speed of longitudinal travel is reduced. The stitching operation includes: rst; the formation or the first fly-barring stitches, after which the follower pin 68 passes out of the offset portion c of the cam groove 66; second; the stitching along one of the straight sides of the buttonhole, during which the follower pin 69 travels rearwardly in the straight portion a of the cam groove 61; third; the stitching around the eye end of the buttonhole, during which the roller 13 is beyond the outer end of the grooveA 14, the lateral movements of the stitching frame are controlled by the cam groove 56 in the main cam 53, the turrets 5| and 52 are given a semirotation, and the direction of longitudinal travel of the stitching frame is reversed; fourth; the stitching along the other straight side of the buttonhole, during which the pin 66 travels forwardly in the straight portion a of the groove 61; and, fth; the completion of the fly-bar, during which the pin 69 traverses the offset portion c' of the groove 61. Thereafter the latch 41 engages the shoulder 46 of the cam bar 43, the stitching mechanism is stopped, the stitching frame moved rapidly forwardly into its initial or buttonhole cutting position (the pin 66 at this time moving forwardly in the straight portion a of the groove 66), the turrets 5| and 52 returned to their original angular position, and the machine stopped. rfliese operations are all substantially as more fully described in Patent No. 2,072,991, above referred to.

At the beginning of the stitching operation, the tube |26 is in the position shown in Fig. 17, presenting an end C of the stay cord C immediately over the needle opening ||1 in the throat plate ||6 in a position to be caught by the first stitches. Thereafter, as the stitching progresses, the cord is drawn through the tube (this being permitted by the `gripping jaw |36), is laid around the edge of the buttonhole, and is bound in by the stitches, as indicated in Figs. 13, 15 and 21.

During the major portion of the rearward movement of the stitching frame, and the formation of the first fly-barring stitches, the stitching along the first straightside of the buttonhole,

and the beginning of the stitching around the eye end, the turret 52 is in the angular position shown in Fig. 4, and the stud |34, roller |60, and stud. |81 are out of operative relation with the lever |36, slide |62, and lever |88, respectively, so that during this movement the operationl of said lever |36, slide |62, and lever |88 by their respective cams |40, |61, and |9| is an idle one and has no effect on the cord supplying, cord cutting, and thread trimming instrumentalities. When the turret 52 is given its semi-rotation in stitching aroundV the eye end of the buttonhole, into the position shown in Fig. 10, the stud |34 is brought into the path of movement of the lever |36, the roller |60 is engaged between the lips |6I of the slide |62, and the stud |61 is brought into the path of movement of the lever |88. During the forward, or return, movement of thestitching frame, at a suitable point prior to the completion of the stitching operation,l the outer end of the lever |36 engages the cam |40 (see Fig. 11) rocking said lever and causing the tube |26 to move from the position shown in Fig. 13 intoV that shown in Fig. 15, as hereinbefore more fully'described. As the tube is so moved, it slides over the cord C (this being permitted by the gripping jaw |39) which is held by the stitches as shown by said figures, leaving a length C2 of cord extending from the stitching tothe end of the tube and between the shear blades |5l. Immediately thereafter, the roller` |66, carried by the slide |62, engages the cam |61, thereby depressing said slide and operating the shears |5| (Fig. 16) to sever the cord, as hereinbefore more fully explained. The arrangement is such that the portion ofthe length C2 of the cord cut from the supply and extending from the last stitches is just sufcient to complete the buttonhole and have its end bound in bythe inal stitches, as shown by Fig. 21, this being determined bythe spacing of the shears |5| from the needle opening ||1 in the. throat plate in conjunction With the longitudinal position of the cam |61 with reference to the end of the stitching as, in turn, determined by the longitudinal position of the cam bar 43, so that the mechanism operates to measure and cut off a length of stay cord in accordance with the length of the buttonhole. In other words the cams 43 and |61 are so located that the movement of the stitching head after theV operation of the shearsV and prior tothe stopping of the stitching mechanism is at least substantially equal to the longitudinal spacing of the shears from the stitching point, so that the length of the free end of cord cut off is no greater, and preferably slightly less than the length of stitching still to be completed. After the'cord has been severed, the tube |26 is returned to the position shown in Fig. 17, carrying the cord with it (due to the action of the gripping jaw |39), and presenting a new end C in suitable position for the starting of another buttonhole. After the completion of the stitching operation, and when the parts have moved in'to substantially the relative position shown in Fig. 23, the lever |68 engages the cam |9| to cause the thread trimming instrumentalities to sever the threads tand t', and to cause the pull-off 201 to draw suiicient under thread fromr the supply to start the sewing of the next buttonhole, allas hereinbefore fully described.

The bracket or slide |42, by which the cams` |40, |61 and |9| are carried, is slidably received (see Fig. 5) .between the bottom surface of the bed frame .30 and aA gib` 22| .(see also Figs. 1 andv 11) adjustably secured to the bracket |45 previously referred to, said bracket or slide |42 being adjustably secured, by a screw 222 to the forward end of the link 9|. Accordingly, when the cam bar 43 and cam plate 65 are adjusted to vary the length of the buttonhole, as above described, the cams |40, |61 and |9| will be simultaneously and correspondingly adjusted, so that the relative time of action of the various mechanisms is maintained regardless of the length of the buttonhole, thus insuring the same trimming action on each size of buttonhole by a single, simple adjustment. The gib 22| is adjustably supported from the bracket |45 on abutment screws 223 (Fig. 11) and is secured in adjusted position to said bracket by screws 224 which pass through slots in said gib, through openings in said bracket and into threaded holes in the stitching frame whereby said bracket is secured to said frame.

It will be observed that, due to the engagement of the legs d and d (Figs. 25 and 26) of the needle thread loop L by the hook |32 at a predetermined point, or in a predetermined position of the stitching frame after the completion of the stitching, at whatever point in the longitudinal travel this may occur, the breaking of the leg d, whether over the edge of the upper face b of said hook, or at the knot or last stitch, as above explained, will take place at a substantially constant point in definite relation to the end of the buttonhole, irrespective of the length of the latter. Consequently, the leg d leading to the needle will likewise be of a definite length, irrespective of the length of the buttonhole, and the arrangement is such that the length of thread so provided or supplied will be suitably measured to start the stitching (i. e., form the rst stitch) of another buttonhole, irrespective of the length of the buttonhole previously sewn. Similarly, the under thread t is severed at a substantially constant distance from the last stitch, irrespective of the position of the latter as determined by the length of the buttonhole, and just prior to such severing the pull-off 2437 draws from the supply a length of under thread which is likewise suitably measured to start the stitching of the neXt buttonhole.

If desired, the under thread cutter |84 may be omitted, in which case only the needle thread will be severed, or by making the hook |32 of such shape that its. movement will not stretch the needle thread suiciently to break the same, only the under thread will be severed.

I claim:

l. A buttonhole sewing machine comprising, in combination, stitching mechanism and workholding means relatively movable to position the stitches lengthwise of the buttonhole, a stop mechanism associated with said stitching mechanism for controlling the operation of the latter, a cam associated with said work-holding means and cooperating with said stop mechanism to stop the operation of said stitching mechanism at a predetermined point during the relative movement and thereby determine the length of the buttonhole, said cam being adjustable to vary said length, trimming mechanism, and a cam for causing operation of said trimming mechanism, said last named cam being connected and adjustable with said rst named cam.

2. A buttonhole sewing machine comprising, in combination, stitching mechanism including a needle and a cooperating looper device on opposite sides of the work, respectively, means for controlling the operation of said stitching mechanism and thereby determining the length of the buttonhole, said means being adjustable to vary said length, thread trimming mechanism located and operating on the looper side of the work, means for causing operation of said trimming mechanism adjustable to determine the time of such operation, and means connecting said last named means with said controlling means for adjustment therewith.

3. A buttonhole sewing machine comprising, in combination, stitching mechanism, means for controlling the operation of said stitching mechanism and thereby determining the length of the buttonhole, said means being adjustable to vary said length, means for supplying a stay cord, means for trimming said cord, means for causing operation of said trimming mechanism adjustable to determine the time of such operation, and means connecting said last named means with said controlling means for adjustment therewith.

A buttonhole sewing machine comprising, in combination, stitchingv mechanism and workholding means, means for causing relative movement or said stitching mechanism and workholding means lengthwise of the buttonhole, rst in one direction and then in the other, trimming mechanism, and means operated `by said relative movement vfor Y operating said trimming mechanism, said last named means being inoperative to operate the trimming mechanism during the relative movement in said nrst direction.

5. A buttonhole sewing machine comprising, in combination, stitching mechanism and workholling means, said stitching mechanism including, in part, a rotary turret and stitch-forming instrumentalities carried thereby, means v for causing relative movement of said stitching mechanism and work-holding means lengthwise of the buttonhole, nrst in one direction and then in the other, means for changing the angular position of said turret with respect to the other parts of said stitchingmechanism when the direction of said relative movement is reversed, trimming instrnmentalities carried by said turret, actuating means for saidl trimming instrumentalities associated with said other parts of the stitching mechanism, said trimming instrumentalities and actuating means being disconnected when said turret is in its angular position during said relaA- tive movement in the first direction but being operatively connected when said angular position is changed during the reversal of said movement, and a cam associated with said Workholding means and engaged by said actuating means, to operate the latter, at a predetermined time during said relative movement.

6. A buttonhole sewing machine comprising, in combination, stitching' mechanism and workholding means, means for causing relative movement of said stitching mechanism and workholding means lengthwise of the buttonhole, first in one direction and then in the other to position the stitches rst along one side of` the buttonhole and then along the other, means for starting and stopping said stitching mechanism, means for controllingsaid starting and stopping means to determine the points during said relative movement when said stitching mechanism is started and stopped and thereby determine the length of the buttonhole, said controlling means being adjustable to vary said length, means for supplying a stay cord to'be sewed in place by said stitching mechanism, mechanism for trimming said cord, and means Vfor actuating said trimming mechanism operated by and at a predetermined time during said relative movement, sai-:i actuating means including a part connected and adjustable with said controlling means to vary said time in accordance with the length of the buttonhole.

'7. In a buttonhole sewing machine, the combination with stitching mechanism and means for controlling said stitching mechanism to determine the length of the buttonhole sewn, said controlling means being adjustable to vary said length, oi mechanism for supplying a stay cord to be secured in place by said stitching mechanism and including means responsive in its action to the length oi the buttonhole as determined by said controlling means for cutting from the supply a length of cord predetermined in accordanee with the length of the buttonhole,

8. In a buttonhole sewing machine, the combination with stitching mechanism and means for controlling said stitching mechanism to determine the length of the buttonhole sewn, said controlling means being adjustable to vary said length, of mechanism for supplying a stay cord tov be secured in place by said stitching mechanism and including means, having a controlling element connected and adjustable with said stitching mechanism controlling means, and thereby rendered responsive to the length of the buttonhole as determined by said controlling means, for cutting from the supply a length of cord predetermined in accordance with the length of the buttonhole.

9. In a buttonhole sewing machine, the combination with stitching mechanism and means for controlling the period of operation of said stitching mechanism to determine the length of the buttonhole sewn, said controlling means being adjustable to vary said length, of mechanism for supplying a stay cord to be secured in place by said stitching mechanism and including means, responsive in its action to the length of the buttonhole as determined by said controlling means and operating prior to the completion of the stitching operation, for cutting from the supply a length oi cord predetermined in accordance with the length of the buttonhole.

10. In a buttonhole sewing machine, in combination, stitching mechanism for sewing around a buttonhole, iirst along one side and thereafter along the second side, means for starting and stopping said stitching mechanism to cause the same to form stitches around a buttonhole oi predetermined length, means for supplying a stay cord in position to be secured in place around the buttonhole by said stitches when said stitching mechanism is in operation, means for severing said cord, and means acting in timed relation with said starting and stopping means for operating said severing means during the sewing along the second side of the buttonhole at a predetermined time prior to the stopping of said stitching mechanism.

11. In a buttonhole sewing machine the combination with stitching mechanism and controlling means for causing said stitching mechanism to operate to perform a stitching operation of predetermined duration to sew a buttonhole of predetermined length, said controlling means being adjustable to vary said duration and consequently the length of the buttonhole, of means for supplying a stay cord to be secured in place by said stitching mechanism, means for cutting said cord, means for operating said cutting means prior to the completion of the stitching operation, and means connecting said last named means with said controlling means for adjustment therewith.

l2. In a buttonhole sewing machine, the combination with stitching mechanism and means for operating the same to perform a stitching operation of variable duration, of means for supplying a stay cord to be secured in place by the stitching mechanism, means for cutting said cord, and means, timed to act in accordance with the duration of the stitching operation, for operating said cutting means at a deiinite time'prior to the completion of the stitching operation irrespective of the duration of the latter.

13. In a buttonhole sewing machine, in combination, stitching mechanism having a throat plate associated therewith, a rigid stay cord guide normally positioned with its delivery end adjacent said throat plate, means to withdraw said guide from its normal position, and means for cutting the cord between said throat plate and guide when the latter is so withdrawn.

i4. In a buttonhole sewing machine, the'combination with stitching mechanism and means for operating the same to perform a stitching operation around a buttonhole, of a stay cord guide normally positioned with its delivery end adjacent the stitching point, means acting prior to the completion of said stitching operation to withdraw said guide from the stitching point, and means acting when said guide is so Withdrawn to cut said cord between said guide and the stitching point.

l5. In a buttonhole sewing machine, sewing instrumentalities and work holding means relatively movable to sew around the contour of a buttonhole and having means, including a stay cord guide, to lay and stitch in a cord around the edge of the buttonhole, cord severing instrumentali-ties, means for relatively so positioning said severing instrumentalities and cord guiding means during the stitching operation that the cord severing instrumentalities can operate, and means for operating the cord severing instrumentalities during the stitching operation, said cord guiding means having means to maintain control of the cord after the severing takes place.y

i6. In a buttonhole sewing machine, in combination, stitching mechanism including a needle and cooperating under thread handling devices, a throat plate having an opening through which the needle passes, means for operating said stitching mechanism to perform a stitching operation around a buttonhole, a pair of normally open shear blades spaced from said throat plate opening, a stay cord guide normally positioned between said blades with its delivery end adjacent said throat plate opening, means acting prior to the completion of the stitching operation to withdraw said guide from between said shear biades, and means for thereupon closing said shear blades to cut the cord between said guide and throat plate opening.

1'?. In a buttonhole sewing machine, in combination, stitching mechanism and work-holding means, means for causing relative movement or" said stitching mechanism and work-holding means successively in opposite directions lengthwise of the buttonhole to position the stitches rst along one side and thereafter along the second y side of the buttonhole, means for starting and stopping said stitching mechanism, means for controlling said starting and stopping means to determine the points during said relative movement when said stitching mechanism is startedand stopped, means for supplying a stay cord, ,means for cutting said cord, and means operated by said relative movement for operating said Ecutting means during the sewing along the second side of the buttonhole at a predetermined time priorto the stopping of said stitching mechanism.

18. In a buttonhole sewing machine, in combination, stitching mechanism and work-holding means, means for causing relative movement of said stitching mechanism and work-holding means lengthwise of the buttonhole to position the stitches therealong, means for starting and stopping said stitching mechanism, means for controlling said starting and stopping means to determine the points during said relative movement when said stitching mechanism is started and stopped, said controlling means being adiustable to vary said points, means for supplying a stay cord, means for cutting said cord, and means operated by said relative movement for operating said cutting means prior to the stopping of said stitching mechanism, said operating means including a controlling element connected and adjustable with said controlling means.

19. In a buttonhole sewing machine, in combination, stitching mechanism and work-holding means, means for causing relative movement of said stitching mechanism and work-holding means lengthwise of the buttonhole to position the stitches therealong, means for starting and stopping said stitching mechanism, a cam associ'ated with said work-holding means for controlling s'aid 'starting 'and stopping means to determine the points during said relative movement when said stitching mechanism is started and stopped, said cam being adjustable in the direction of said relative movement, means for supplying a stay cord, means for cutting said cord, and means operated by said relative movement for operating vsaid cutting means prior to the stopping of said 'stitching mechanism, said operating means including a cam associated with said work-holding means and connected and adjustable with 'said 'rst named cam. 20. In a buttonhole sewing machine, in combination, stitching mechanism and work-holding means, means for causing relative movement of said stitching mechanism and work-holding means to position the stitches, means associated with said stitching mechanism for starting and stopping the latter, means including a member associated with said work-holding means and covacting with said starting and stopping means during said relative movement to determine the points in said movement when the stitching mechanism is started and stopped, means associated with said stitching mechanism for supplying a stay cord to be secured in place by said stitching mechanism, means likewise associated with said stitching mechanism for cutting said cord, said cutting means being spaced from the stitching point in the direction of said relative movement, and means including a member associated with said work-holding means 'and coacting with said cutting means during said relative movement to actuate said cutting means, said members being so located that the amount of relative movement subsequent to the operation of said cutting means and prior to the stopping of said stitching mechanism is at least substantially equal to the spacing of the cutting means from the stitching point.

21. In a buttonhole sewing machine, the combination with stitching mechanism including a needle and a cooperating looper device on op- CII posite sides of the work, respectively, and means for operating and controlling said stitching mechanism to cause it to perform automatically stitching operations of variable duration to sew buttonholes of different lengths, of means located and operating on the looper side of the work for trimming the sewing thread adjacent the work, and means responsive in its action to the length of the buttonhole as determined by said controlling means for automatically actuating said trimming means at the completion of a stitching operation irrespective of the duration of the latter.

22. In a buttonhole sewing machine, the combination with stitching mechanismincluding a needle and a cooperating looper device on opposite sides of the work, respectively, and means for oper-ating and controlling said stitching mechanism to cause it to perform automatically stitching operations of variable duration to sew buttonholes of diierent lengths, said means including an adjustable controlling member for determining the end of the stitching operation, and means located and operating on the looper side of the work for trimming the sewing thread adjacent the Work, means for actuating said trimming means at the completion of a stitching operation irrespective of the duration of the latter, said actuating means including an adjustable controlling member, and means connecting said last named controlling member with said rst named controlling member for adjustment therewith.

23. In a buttonhole sewing machine, the combination with stitching mechanism including a needle and a cooperating looper device on opposite sides of the work, respectively, and means for operating and controlling said stitching mechanism to cause it to perform automatically stitching operations of variable duration to sew buttonholes of different lengths, of means located and operating on the looper side of the work for trimming the sewing thread adjacent lthe work, and means responsive in its action to the length of the buttonhole as determined by said controlling means for automatically actuating said trimming means to cut the thread at a fixed point relative to the end of the buttonhole irrespective of the length of the latter.

24. In a buttonhole sewing machine, in vccmbination, stitching mechanism and work-holding means, means for causing relative movement of said stitching mechanism and work-holding means lengthwise of the buttonhole, means associated with said stitching mechanism for starting and stopping the same, a controlling member associated with said work-holding means and cooperating with said starting and stopping means for determining the time during said relative movement when the stitching mechanism starts and stops, thereby determining the length of the buttonhole, said member being adjustable to vary said length, mechanism associated with said stitching mechanism for trimming the sewing thread, and a member associated with said work-holding means and engaged by a portion of said trimming mechanism during said relative movement to actuate said trimming mechanism, said last named member being connected and adjustable with said rst named controlling member.

25. In a sewing machine, in combination, stitching mechanism operative to perform a stitching operation and stop, said stitching mechanism including a needle supplying an upper thread and cooperating under thread mechanism supplying an under thread, a single thread trimmer carrying a cutter and having a beak and faces diverging therefrom one of which faces leads tosaid cutter, and means operated upon the completion of said stitching operation for so actuating said trimmer as to move said beak between said upper and under threads, whereby said one face forces the under thread against said cutter and the other face deflects the upper thread and ultimately breaks the same.

26. In a buttonhole sewing machine, in combination, stitching mechanism operative to perform a stitching operation and stop, said stitching mechanism including a needle supplying an upper thread and cooperating under thread mechanism supplying an under thread, work-holding means, means for causing relative movement of said stitching mechanism and work-holding means into and out of stitching position, means associated with said stitching mechanism for separating the upper and under threads during Vsaid relative movement outl of ystitching position, and means for thereafter trimming said threads.

2'7. In a buttonhole sewing machine, in combination, stitching mechanism operative to perform a stitching operation 'and stop, said stitching mechanism including a needle supplying an upper thread and cooperating under thread mechanism supplying an under thread, work-holding means, means for causing relative movement of said stitching mechanism and work-holding means into and out of stitching position, a throat plate associated with said stitching mechanism and having a portion formed to separate the upper and under threads during said relative movement out of stitching position, and means for thereafter trimming said threads.

28. In a buttonhole sewing machine, in combination, stitching mechanism operative to perform a stitching operation and stop, said stitching mechanism including a needle supplying an upper thread and cooperating under thread mechanism fsupplying an under thread, work-holding means, means for causing relative movement of said stitching mechanism and work-holding means into and out of stitching position, 'a throat plate associated with said stitching mechanism and having two grooves adapted, during said relative movement out of stitching position, to receive the upper and under threads, respectively, and separate the same, a thread trimmer, and means operated upon the completion of said stitching operation, for moving said trimmer between the separated threads, further separating and severing the same.

29. In a buttonhole sewing machine, in combination, stitching mechanism, means for operating the same to perform a stitching operation around a buttonhole and stop, said stitching mechanism including a needle for passing loops of thread through the work and cooperating looper means for taking said loops, a thread deflecting member movable in a path across a needle loop held b-y said looper means and having a portion arranged to engage both legs of said loop when so moved, land means acting upon the completion of said stitching operation, to move said deflecting member to force said portion against both legs of said loop and thereby deflect said legs and tension the same suiiiciently to cause breakage of the shorter leg leading to the work.

30. In a sewing machine, in combination, stitching mechanism including a needle supplying an upper thread and cooperating under thread mechanism supplying an under thread, thread trimming mechanism, a single combined tensioning and pull-01T device for the under thread, vand a connection between said device and said trimming mechanism for operating the former from the latter.

31. In a buttonhole sewing machine, in combination, stitching mechanism including a needle supplying an upper thread and cooperating under thread mechanism supplying an under thread, work-holding means, means for causing a relative movement of said stitching mechanism and Workholding means lengthwise of the buttonhole, thread trimming mechanism operated by said relative movement, and a combined tensioning device and pull-oil? for the under thread operated by said trimming mechanism.

32. In a sewing machine, in combination, stitching mechanism operative to `perform apredetermined stitching operation and including a needle supplying an upper thread and cooperating under thread mechanism supplying an under thread, a thread guide from which the under thread is led to said under thread mechanism, a thread handling device comprising a pivoted lever having adjacent its pivot a thread deflecting member and adjacent its free end a normally open thread clamp through which the under thread normally passes freely from said thread guide to said under thread mechanism, and an actuator operative at the end of the stitching operation to swing said thread handling device on its pivot, close said clamp, deflect -the under thread about said deflecting member, and pull thread directly from said thread guide.

33. In a sewing machine, in combination, stitching mechanism operative to perform aprevdetermined stitching operation and including a needle supplying an upper thread and cooperating under thread mechanism supplying an under thread, a thread guide from which the under thread is led to said under thread mechanism, a thread handling device comprising a pivoted lever having adjacent its pivot a thread deflecting member and adjacent its free end a normally open thread clamp through which the under thread normally passes freely from said thread guide to said under thread mechanism, a thread trimmer, and a lever operative at the end of the stitching operation to operate said thread trimmer and having an extension provided with means to swing said thread handling device on its pivot, close said clamp, deflect the under thread about said defiecting member, and pull thread directly from said thread guide.

34. In a Abuttonhole sewing machine, in combination, stitching mechanism, means for operating the same to sew a buttonhole having a fly bar, controlling means for said operating means adjustable to cause said stitching mechanism to sew automatically buttonholes of different lengths while maintaining constant the length of the fly bars, means for supplying a stay cord to be sewn in around the buttonhole by the stitching mechanism, means for severing said cord from the supply, and cooperating mechanism positioned by the adjustment of the controlling means for automatically operating said severing means.

35. In a buttonhole sewing machine, in combination, stitching mechanism, means for operating the same to sew a buttonhole having a ily bar, controlling means for said operating means adjustable to cause said stitching mechanism to sew automatically buttonholes of different lengths with fly bars of different lengths', means for supplying a stay cord to be sewn in around the buttonhole by the stitching mechanism, means for severing said cord from the supply, and cooperating mechanism positioned by the adjustment of the controlling means for automatically operating said severing means prior to the completion of the stitching operation.

36. In a buttonhole sewing machine, in combination, stitching mechanism, work-holding means, means for causing relative movement of said stitching mechanism and work-holding means lengthwise of the buttonhole, means operated by said relative movement for controlling said stitching mechanism, said controlling means being adjustable in the direction of said relative movement to cause said stitching mechanism to perform automatically stitching operations of variable duration during said relative movement to sew buttonholes of different lengths, trimming mechanism, and means also operated by said relative movement for operating said trimming mechanism, said last named means including a controlling element also adjustable in the direction of said relative movement to cause automatic operation of said trimming mechanism at a Variable time in said relative movement in accordance with the duration of the stitching operation.

37. In a sewing machine, in combination, stitching mechanism including a needle and cooperating under thread instrumentalities through which an under thread is supplied, under thread trimming mechanism, a device engaging and coacting with the under thread leading to said instrumentalities, said device being movable into Vsuccessive positions, rst, to tension the thread for the action of the trimming mechanism and, second, to pull 01T a predetermined amount of thread from the supply without increasing said tension, and means for so moving said device.

38. In a sewing machine, in combination, stitching mechanism including a needle and cooperating under thread instrumentalities through which an under thread is supplied, under thread trimming mechanism, a device engaging and coacting with the under thread leading to said instrumentalities, said device being movable into successive positions, rst, to tension the thread for the action of the trimming mechanism and, second, to pull off a predetermined amount of thread from the supply without increasing said tension, and a connection between said device and said trimming mechanism for so moving said device.

39. In a buttonhole sewing machine, in combination, stitching mechanism and work-holding means, means for causing relative movement of said stitching mechanism and work-holding means lengthwise of the buttonhole to position the stitches therealong, means operated by said relative movement for starting and stopping said stitching mechanism, means adjustable in the direction of said relative movement for controlling said starting and stopping means to determine the points during said relative movement when said stitching mechanism is started and stopped, means for trimming the sewing thread, and means likewise operated by said relative movement, and including controlling means also adjustable in the direction of said movement, for operating said trimming means immediately upon the stopping of said stitching mechanism.

49. In a buttonhole sewing machine, in combination, stitching mechanism and work-holding means, means for causing relative movement of said stitching mechanism and work-holding means lengthwise of the buttonhole to position the stitches therealong, means operated by said relative movement for starting and stopping said stitching mechanism, means adjustable in the direction of said relative movement for controlling said starting and stopping means to determine the points during said relative movement when said stitching mechanism is started and stopped, means for supplying a stay cord, means for cutting said cord, and means likewise operated by said relative movement, and including controlling means also adjustable in the direction of said -movement, for operating said cutting means prior to the stopping of said stitching mechanism.

41. In a buttonhole sewing machine, in combination, stitching mechanism and work-holding means, means for causing relative movement of said stitching mechanism and work-holding means lengthwise of the buttonhole to position the stitches therealong, means for starting and stopping said stitching mechanism, means for controlling said starting and stopping means to determine the points during said relative movement when said stitching mechanism is started and stopped and thereby determine the length of the buttonhole, said controlling means being adjustable to vary said length, means for trimming the sewing thread, and means operated by said relative movement for operating said trimming means, said last named means being likewise adjustable to cause operation of said trimming means immediately upon the stopping of said stitching mechanism as determined by the adjustment of said controlling means.

42. In a buttonhole sewing machine, in combination, stitching mechanism and work-holding means, means for causing relative movement 0I" said stitching mechanism and work-holding means lengthwise of the buttonhole to position the stitches therealong, means for starting and stopping said stitching mechanism, means for controlling said starting and stopping means to determine the points during said relative movement when said stitching mechanism is started and stopped and thereby determine the length of the buttonhole, said controlling means being acljustable to vary said length, means for supplying a stay cord, means for cutting said cord, and means operated by said relative movement for operating said cutting means, said last named means being likewise adjustable to cause operation of said cutting means prior to the stopping of said stitching mechanism as determined by the adjustment of said controlling means.

JOSEPH H. PIKUL. 

